There has been a lot of controversy about artificial sweeteners and weight. The epidemic of childhood obesity has been linked to increased soda consumption. Sodas and sweetened beverages like sports drinks and flavored teas have surpassed white bread as the number one source of calories in the American diet. A six month study done at Children’s Hospital in Boston followed two groups of teenagers. The study, published in the journal Pediatrics, compared teenagers who substituted sugar-sweetened beverages for bottled water or artificially-sweetened drinks with teenagers who continued to consume their usual amount of soda and sweetened drinks. The study found that the teenagers that consumed diet soda lost weight and the teenagers that drank normal soda gained weight. The researchers estimated that one 12-oz regular soda per day will lead to about one pound of weight gain in a month.
There is also research that suggests that artificial sweeteners can make you gain weight. Although promoted to help you lose weight, artificial sweeteners like sucralose (Splenda), aspartame (NutraSweet and Equal), or saccharin (Sweet’n Low) may interfere with your efforts to lose weight by confusing your body and disrupting hormonal balance. Critics claim that sugar substitutes sabotage the body’s ability to monitor food intake based on a food’s taste. This makes people more likely to overindulge in other foods. People who crave sweets turn to artificial sweeteners as a way of helping their sugar cravings, but they may make the cravings worse. They drink a diet soda and later in the day they are ravenous and craving sweets. Many people find that when they stop using sugar substitutes, their carbohydrate cravings stop.
A 2004 Purdue University study published in the International Journal of Obesity showed that artificial sweeteners can cause weight gain in rats. In the study, rats were fed foods with artificial sweeteners. They were compared to a second group of rats that did not receive artificial sweeteners. The rats that consumed artificial sweeteners ate more food overall and gained weight. The rats that were not fed artificial sweeteners did not gain weight. The researchers concluded that artificial sweeteners made the rats gain weight because it was tricking the rats’ brains, stimulating appetite.
Researchers in at the Centre for Advanced Food Studies in Denmark performed a similar study on humans. Two groups of people were fed identical diets in a research setting. The only difference was that one group was served beverages with artificial sweeteners and the other group was served beverages that were sweetened with real sugar. The people who had artificial sweeteners ate more food than the people who had real sugar. Unlike the rats, however, the people who drank beverages with real sugar consumed more calories and gained weight and the people who drank artificially sweetened drinks, lost weight. The overall result of the study was the opposite of the rats. At the end of ten weeks, the people who had artificial sweeteners lost about two pounds and the people who had regular sugar drinks gained about three pounds.
These studies show that when you consume artificial sweeteners, your body craves more food. But humans are not rats. If you can’t judge the calorie content of a particular food based on its sweetness, you are more likely to overeat. This is why it is so important to read the labels. The food industry does more to alter food than just adding artificial sweeteners. Fat free products may cause the same effect. When manufacturers reduce the fat content in foods, they usually increase the sugar to compensate. For example, fat-free ice cream is usually higher in sugar content; sugar-free ice cream is usually higher in fat content. Sugar free or fat free does not mean calorie free and many times the regular counterpart has less calories and tastes better.
It is a problem if you drink more than one or two artificially sweetened beverages on a daily basis. A study presented at the 2005 American Diabetes Association meeting estimates that your risk of being overweight goes up 65% for every diet soda you drink each day. If you consume a lot of artificial sweeteners, you may have increased appetite and are more likely to overeat other foods. Humans have a major advantage over rats. Rats can’t read labels. You have to read labels to find out how many calories are in the food you eat.
There is still a lot of disagreement among experts regarding artificial sweeteners. My recommendation is to limit your consumption of diet drinks to no more than one or two cans per day. I recommend that you drink mostly water or unsweetened, low calorie beverages like iced tea or club soda. If you need to sweeten your coffee or tea, use a little bit of real sugar or honey, just don’t overdo it. Sodas and other sugary beverages have no nutritional value and should be avoided altogether.
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